/*
 * Ext JS Library 3.0 RC2
 * Copyright(c) 2006-2009, Ext JS, LLC.
 * licensing@extjs.com
 * 
 * http://extjs.com/license
 */

/* Fix for Opera, which does not seem to include the map function on Array's */
if(!Array.prototype.map){
    Array.prototype.map = function(fun){
	var len = this.length;
	if(typeof fun != "function"){
	    throw new TypeError();
	}
	var res = new Array(len);
	var thisp = arguments[1];
	for(var i = 0; i < len; i++){
	    if(i in this){
		res[i] = fun.call(thisp, this[i], i, this);
	    }
	}
        return res;
     };
}

/* Paging Memory Proxy, allows to use paging grid with in memory dataset */
Ext.ux.PagingMemoryProxy = Ext.extend(Ext.data.MemoryProxy, {
    constructor: function(data) {
	Ext.ux.PagingMemoryProxy.superclass.constructor.call(this);
	this.data = data;
    },
    doRequest : function(action, rs, params, reader, callback, scope, options) {
	params = params || {};
	var result;
	try {
	    result = reader.readRecords(this.data);
	}catch(e){
	    this.fireEvent("loadexception", this, options, null, e);
	    callback.call(scope, null, options, false);
	    return;
	}
	
	// filtering
	if (params.filter!==undefined) {
	    result.records = result.records.filter(function(el){
		if (typeof(el)=="object"){
		    var att = params.filterCol || 0;
		    return String(el.data[att]).match(params.filter) ? true : false;
		} else {
		    return String(el).match(params.filter) ? true : false;
		}
	    });
	    result.totalRecords = result.records.length;
	}
	
	// sorting
	if (params.sort !== undefined) {
	    // use integer as params.sort to specify column, since arrays are not named
	    // params.sort=0; would also match a array without columns
	    var dir = String(params.dir).toUpperCase() == "DESC" ? -1 : 1;
	    var fn = function(r1, r2){
		return r1 < r2;
	    };
	    result.records.sort(function(a, b) {
		var v = 0;
		if (typeof(a)=="object"){
		    v = fn(a.data[params.sort], b.data[params.sort]) * dir;
		} else {
		    v = fn(a, b) * dir;
		}
		if (v == 0) {
		    v = (a.index < b.index ? -1 : 1);
		}
		return v;
	    });
	}
	// paging (use undefined cause start can also be 0 (thus false))
	if (params.start !== undefined && params.limit !== undefined) {
	    result.records = result.records.slice(params.start, params.start+params.limit);
	}		
	callback.call(scope, result, options, true);
    }
});
//backwards compat.
Ext.data.PagingMemoryProxy = Ext.ux.PagingMemoryProxy;
